The New Zealand First leader has been one of the big winners of the "teapot tapes" saga, after it was alleged Prime Minister John Key made disparaging remarks about the party and its elderly support base.

While Mr Peters refused to say whether he had listened to the possibly illegal recording of the talk between Mr Key and ACT Party Epsom candidate John Banks, he said he knew what was on the tape.

Mr Peters mentioned Mr Key's alleged comments during a speech in Whangarei yesterday. Later, he blasted Mr Key for walking out of a press conference after repeated questioning about the tapes.

"Losing his rag and spitting the dummy is not really what you expect," he said.

Mr Peters, who is hoping to return from the electoral wilderness after missing the 5 per cent threshold in 2008, will speak at the Invercargill Workingmen's Club from 2pm. He will be at the Southern Institute of Technology from noon, with a walkabout in the city centre from 1pm.

His party is currently sitting on about 3 per cent of the party vote. With Mr Peters not standing in an electorate seat, it requires 5 per cent of the party vote to gain a presence in Parliament.